Recently, a Time and Wavelength Division Multiplexed-Passive Optical Network (TWDM-PON) has been regarded as a primary solution to the Next Generation-Passive Optical Network (NG-PON2) in the standard meeting hosted by the FSAN. Multiple XG-PONs (10 Gbit PONs or 10G Passive Optical Networks) are stacked into a TWDM-PON system. Besides the ITU-T G.multi working team also proposes Multiple Wavelength-Passive Optical Network (MW-PON), which is a stack of several Time Division Multiplexed-Passive Optical Networks (TDM-PONs) by assigning a different wavelength to each TDM PON in a single Optical Distribution Network (ODN). The TDM-PONs include an E-PON, a G-PON, an XG-PON, etc., all of which will be referred simply to as a PON. Thus the TWDM-PON system can be regarded as an MW-PON system. In the MW-PON system, a plurality of PONs share an ODN through time and wavelength division, and an ONU can tune its own wavelength to be connected to a corresponding PON.
In the MW-PON system, a plurality of PON systems share an ODN so as to lower the cost of network deployment and maintenance. However in the existing MW-PON system, each PON is consisted of an Optical Line Terminal (OLT) and a plurality of ONUs connected therewith, and the connections between the OLT and the ONUs are fixed. Consequently the existing MW-PON system is architecturally inflexible.